#include<iostream>

using namespace std;

int gcd(int x, int y) {
	if(y == 0) {
		return x;
	} else {
		return gcd(y, x % y);
	}
}

int main(void) {
	
	int a, b;
	cin >> a >> b;
	cout << gcd(a, b) << endl; 
	return 0;
}
